Analysis of Floral Fragrance Compounds of Chimonanthus praecox with Different Floral Colors in Yunnan, China

In order to better understand the floral fragrance compounds of Chimonanthus praecox belonging to genus Chimonanthus of Chimonanaceae in Yunnan, headspace solid-phase microextraction combined with gas chromatography-mass spectrometry was used to analyze these compounds from four C. praecox plants with different floral colors. Thirty-one types of floral fragrance compounds were identified, among which terpenes, alcohols, esters, phenols, and heterocyclic compounds were the main compounds. Interestingly, the floral fragrance compounds identified in the flowers of C. praecox var. concolor included benzyl acetate, alpha-ocimene, eugenol, indole, and benzyl alcohol. By contrast, the floral fragrance compounds beta-ocimene, alpha-ocimene, and trans-beta-ocimene were detected in C. praecox var. patens. Cluster analysis showed that C. praecox var. concolor H1, H2, and C. praecox var. patens H4 were clustered in one group, but C. praecox var. patens H3 was individually clustered in the other group. Additionally, principal component analysis showed that alpha-ocimene, benzyl alcohol, benzyl acetate, cinnamyl acetate, eugenol, and indole were the main floral fragrance compounds that could distinguish the four C. praecox with different floral colors in Yunnan. This study provides a theoretical basis for further elucidating the mechanism and pathway of the floral fragrance release of C. praecox.